1. Field of the Invention
The present invention relates generally to a ball screw, and more particularly, to a deflector for a ball screw.
2. Description of the Related Art
The linear transmission device can allow the machine mounted thereon to definitely and precisely moved, so it is broadly applied to a variety of industries. The common linear transmission device includes ball screw, linear guideway, and linear motor system.
Taking the ball screw as an example, the ball screw includes a screw spindle having a thread formed on its external side, a screw nut sleeved onto the screw spindle, and a plurality of rolling members mounted between the screw spindle and the screw nut. The rolling members are moved synchronously circularly moved by a chain to allow the screw nut for smooth movement and rotation along the screw spindle via the rolling members.
U.S. Pat. No. 5,993,064 disclosed that a flexible ball connector 1 includes a plurality of balls 3 which can allow the ball connector 1 for curvature towards various directions while moving. As shown in FIG. 19 of the aforesaid patent, a nut member 152 further includes a return pipe 154, through which a connector belt 2 and the balls 3 pass and which has guide grooves 157 formed at internal walls thereof for guiding a belt members 5 of the connector belt 2 in such a way that the connector belt 2 and the balls 3 can be more smoothly circularly moved between the nut member 152 and a screw shaft 150. The guide grooves 157 of the return pipe 154 are symmetrically mounted to the internal walls of the return pipe 154 with respect to what a center of the return pipe 54 extends, such that the connector belt 2 can be moved along the guide grooves 157.
As the connector belt 2 is moved, it can twist along with its moving path to enable different deformation states of the belt members 5 in the guide grooves 157. However, the guide grooves 157 in the return pipe 154 have the same cross section, so the connector belt 2 fails to coordinate with the guide grooves 157 and the connector belt 2 is subject to excessive contact with the internal walls of the guide grooves 157. In this way, the belt members 5 and the guide grooves 157 have greater friction therebetween to result in wear and tear of the belt members 5 and reduction of the service life of the connector belt 2.